Scientists have increasingly documented the deadly threat that fishing lines and ropes pose to large whales that become entangled in them. Now, new studies are pointing to another disturbing fact: the enormous pain suffered by whales that become ensnared. READ MORE

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Rescuers throw a grapple to free an entangled whale in the waters north of Provincetown, Mass. The whale, a female with a calf, had fishing line and two buoys tangled on her fluke. While rescuers said this disentanglement should have been relatively easy, they found that healed scars from an earlier entanglement were holding the gear in place. (Provincetown Center for Coastal Studies/NOAA Permit #932-1905)